In recirculating cooling water systems, biofilm formation due to bacterial growth is unavoidable. Standard design practices for such cooling systems specify addition of a biocide to the cooling fluid. However, no biocide retains its antibacterial efficacy indefinitely. Consequently, the cooling fluid has to be periodically sampled for bacterial growth. Where growth exceeds a certain threshold, preventative maintenance is required. Such maintenance may involve actions ranging from draining, flushing, or recharging the coolant loop to hardware replacement in severe cases where biofilm has clogged the heat exchangers. Since bacterial growth rates in the field are difficult to predict, there is a risk of hardware being fouled by biofilms prior to scheduled preventive maintenance.